Project Summary Parasitic nematodes have long harmed crops, pets, livestock, and humans. Wide usage of current broad-spectrum anthelmintics as preventive medicine has led to emerging nematode resistance against these compounds in many human populations, prompting the exploration of compounds with novel genetic targets. Our discovery that an insect pheromone can act both as an attractant as well as an anthelmintic represents a unique opportunity to define a novel drug target. Our proposal is to identify the mode-of-action for this pheromone using a lipid- binding protein as the genetic entry point. We propose three independent strategies involving candidate gene expression and functional analysis, along with forward genetic screens to identify the pheromone receptor and other components of the signaling pathway.